子传父
子
this.$emit('childLoading',this.currentProvince, this.currentCity)
父
<placeList :place-change="placeChange" @childLoading="childLoading" />
placeChange(province, city) {
     console.log(province,city)
}

父传子
父
<son :toSon="msg"></son>
<script>
	import son from './son'
	export default{
		components:{son},
		data(){
			return {
				msg:'信息'
			}
		}
	}
</script>
子
<div>{{sonMsg}}</div>
<script>
	export default{
		// props:['toSon']
		props:{
			toSon:{
				type:String,
				default(){
					return ''
				}
			}
		}
	}
</script>